Collapsible ladder



H. K. SMITH COLLAPSIBLE LADDER Filed Dec. 29, 1927 May 14, 1929.

llatented May 14, 1929.

entre sra'rs Hman ir. sieren, or nnrnorr, ivricncrean".

COLLAPSIBLE LADDER.

Application filed December 939, 1927.

This invention relates to an extensible and collapsible ladder, and itsobject is to provide a construction which is such that the same may beso collapsed as to take up a minimum space, may be quickly manipulated,light in Weight, rigid in construction and cheap to manufacture. Afurther object is to provide an ellicient locking` means for locking therelatively movable parts in the position to Which they are adjusted andwhich locking means is concealed and readily adjustable, and sopositioned as to permit et a maximum extension and collaps ine; movementot the ladder section.

ldith the above and other ends in vie'vv, the invention consists in thematters hereinafter set forth and more particularly pointed out in theappended clair-n, reference being; had to the accompanying dran/'ingl inwhich- Figure l is a liront elevation of the ladder in extended positionwith parts broken away to shorten the figure;

lille". 2 is a similar vieiv showing the ladder in collapsed condition,and

3 is an enlarged sectional vievv of a portion et the ladder showing)`the locking means in elevation.

it ladder embodying?)1 the present invention comprises a series olfsections the side mem bers ol which are preferably olf tubular construction, these members of each section bei oi'i a diameter to lit andslide Within the tubular members et the section below. 'lhc tubular sidemembers o l' each section are connected by a single transverse member orrung` and it is the particular positioning` or connection olf thisrung,` to the side members ci: each section Which permits olf a maximump sing),I movement et the sections.

Els shown in the drawing` a bottom section l comprises tubular sidemembers 2 olf the desired diameter and length and these side members areconnected by transverse tubes il and d, the ends ol' which are rigidlysecured te the side members, preferably by Welding the ends et the tubes3 and l to the adjacent sides of the tubes 2. The overall lengrth of theside members 2 is such that the ladder "when collapsed may be easilyhandled and will not be of such a length as to be unwieldy. The members3 and l form rungs coimectinp,` the side members 2 and the upper rung tis positioned at the extreme upper ends of the members 2. The lower endsof the side members 2 are provided with caps 5 which may be of rubber orother suitable Serial No. $343,296.

material adapted to prot-ect the surlfaco upon which the ladder is setand cover the lower ends ol" the members 2 to prevent them frominjuring,- that surl'ace and also to prevent: the foot el the ladderfrom slippingivvl en it is set up. i

The section G ol'i the ladder directly above the loot section comprisestubular side members 7 oit a diameter to lit and slide `l-reely Withinthe members 2 and these side members 7 are (connected together at theiroxtreme upper ends by means ot' a transverse tubular rung correspondingto the rung` Ll. The section 6 may therefore telescope Within thesection l to nearly its lfull length, or until the rung;` l strikes theupper ends el? the tubes 2.

Sections similar to the section t3 are providedthereabove, each sectionhaving side members 7 et tubular term which are et an external diameterto lit and slide freely Within the tubular side members ot the nextsect-ion below and the ladder is thus made of a series of sections, eacharranged to tele scope Within the section belovv and the number ofsections is such as to provide the desired length for the ladder7 thesingle ruim or transverse member which connects the side members of eachsection being positioned at the extreme upper end oi said side membersto that section so that the maximum olf tele scopie movemciit olf theseveral sections is secured.

'llhe upper ends oit the extreme upper scction may also be provided withknobs t3 simin lar to the knobs to prevent injury to the surface againstwhich the ladder is when the same is in use.

To loch the several sections in, their eX- tended or collapsed position,locking means is housed within each upper rune' el each section saidlockingmeans comprisinp,l a rod 9 adapted to telescope Within a sleeveor tube l0, said rod and tube being positioned and held axially Withinthe rung` l by means ot bearing disks ll Welded or otherwise securedWithin the tubular rung adjacent each end thereof and sleeved upon therod 9 is coiled spring l2 interposed between a laterally eX- tendinglinger piece 18 on the rod and the adjacent end et the sleeve l0, saidsleeve l0 is also provided with a nger piece la at its inner end andthese finger pieces project laterally through a slot in 'the lovver sideof the tubular rung. The outer ends et the rod 9 and sleeve l() areadapted to engage lOO within openings 16 in the tubular side members 7of the section above, the Wall of the tubular side members of thissection below to which the rung 4 is Welded at its ends, beingl cut awayat the end of the rung so that the ends of the rod 9 and sleeve l0 mayengage freely Within these openings 1G and prevent further relativemovement of the sections. When the several sections collapsed ortelescoped, to the position shown in Fig. 2, the ends of the lockingrods and sleeves engage Within the openings in the side members of thesections and thus locl; the several sections in the position to whichthey have been adjusted. VWhen the la -is extended to the position shownin Fig. l rthe rods 9 and sleeves l() of the several loci;-

ing members positioned .vithinthe several rungs, engage other openingsin the side members of the sections and thus hold these sections in theposition to which they are extended.

With this construction and arrangement a very strong ladder is providedwhich may be collapsed into a small space and which is constructedentirely ci: thin tubing, making it very strong and rigid, yet light tohandle. Such a ladder is particularly adapted for use by electriciansand others Working Within a building Where it is necessary to move theladder trom place to place and where it is desirable that such a. laddermay be collapsedl into a small space, further .facilitating itsconvenient handling. By welding the tubular rungs to the tubular sidemembers, the ladder may be cheaply constructed and by locking theserungs at the extreme upper ends of the several sliding sections themaximum of telescopic movement is secured. Further by locking thelocking means Within the several rungs, such locking means is concealedand protected against injury, at the same time facilitating theadjustment thereof and permitting of a maximum ot' collapsing movement,said locking means because of its location Within each rung being out ofthe Way of the adjacent sections where it dees not interfere with thefull collapsing movement of the sections. The only portion of thelocking means Which projects from cach tubular rung, are the ingers 13and la and these fingers extend downwardly through a slot in the rung insuch a position that they do `not interfere with the fullcollapsingmovement of the section above, the rung of that section lyingparallel With and close to the rung of the section below when saidsect-ions are iully collapsed. These iinger Ypieces are alivays in aposition Where they ma be readily grasped by thc operator to Witidrawthe ends of the rod S) and .sleeve 10 from the opening 1G and the springlil exerts torce tending to move the rod and sleeve relatively inopposite directions so that their ends will snap into the openings whenthe sections are moved to brine' the opening 16 into position to be enVthereby.

)bviously the side membeiw: of each avec. tion of the ladder may beother than cylindrical in cross section and the rungs oil die ladder mayhave any desired cross sectional configuration but preferably all etdiese members forming the ladder are tubular. (he side members fortclescoping` niovennini, and the runef members for receiving andconcealA ing the roel-:ing means. Other changes may be made Within the.scope ol the apprnded claim Without departing troni the spirit oi theinvention and l do not theretori` limit myseliI to the particularconstruction shown.

Having thus fully described my inveniiou what I claim is A laddercomprising a toot section having tubular side members connected by aplurality of rungs, the upper of said rangs being tubular and secured atits ends io the side members at the extreme upper end oilt said sidemembers, a series of sections each coniprising tubular side members oi adiameter to iit and slide within the tubular side nie1nbers of theadjacent section below, and said side members being` connected at theirextreme upper ends by a single tubular rung, locking means housed withineach of the tubular rungs and comprising a locking;` rod and a lockingsleeve to receive the :uljacent end of said rod, said rod and sleevehaving laterally projeetinggf iingers and a coiled spring sleeved uponthe rod between the iinger thereon and the end ot the sleeve, saidtubular rung` being formed with a longitudinal slide intermediate itsends through which the fingers proj ect laterally and doivn- Wardly fromthe sleeve and rod, said tubular side members ot each section being`iormcd With openings to receive the ends ot the locking rod and sleeve.and caps on the lower ends of the side men'ibers of the .lower sections.

In testimony whereo't` I ailix my signature.

HIRAM l. SMITH.

lill) liifi

